Systems Analysis & Design: Topic 8
Finalization of the Analysis Phase

INTRODUCTION

Analysis phase:

Phase Name:ANALYSIS
Major Function:To determine the requirements of a proposed new system.
OutputProblem Specification
Principal Toolsfact-gathering techniques
data dictionary
data flow diagrams
process specifications
data models
system models
prototyping
system flowcharts
Warnier-Orr diagrams.
Personnel and Tasks:Users must continue to be heavily involved.
1. The analyst studies and documents the current system in order to understand both its flaws and its strong points.
2. The analyst prepares a list of requirements for a new system.
3. The analyst diagrams the functions of the new system without specifying exactly how those functions are performed.
4. The analyst may prepare a prototype of the system.



CHOOSING SOFTWARE AND HARDWARE

Advantages of commercial software

Disadvantages of a commercial software

When evaluating commercial software consider the following:


Hardware:

Constraints on hardware selection



COST-BENEFIT ANALYSIS

Tangible Benefits:

Intangible Benefits:

Tangible Costs:

Intangible Costs:


Comparing Costs and Benefits

Purpose:

Techniques:

How to Select Most Appropriate Technique:

  1. break-even analysis - used if the project needs to be justified in terms of cost, not benefits, or if benefits do not substantially improve with the proposed system.
  2. payback analysis - used when the improved tangible benefits form a convincing argument for the proposed system.
  3. cash-flow analysis - used when the project is expensive, relative to the size of the company, or when the business would be significantly affected by a large drain on funds.
  4. net present value analysis - used when the payback period is long or when the cost of borrowing money is high.